Gonadoblastoma Y locus genes expressed in germ cells of individuals with dysgenetic gonads and a Y chromosome in their karyotypes include DDX3Y and TSPY.

STUDY QUESTION: Which Y genes mapped to the 'Gonadoblastoma Y (GBY)' locus on human Y chromosome are expressed in germ cells of individuals with some Differences of Sexual Development (DSD) and a Y chromosome in their karyotype (DSD-XY groups)? SUMMARY ANSWER: The GBY candidate genes DDX3Y and TSPY are expressed in the germ cells of DSD-XY patients from distinct etiologies: patients with mixed gonadal dysgenesis (MGD) and sex chromosome mosaics (45,X0/46,XY; 46,XX/46,XY); patients with complete androgen insensitivity (CAIS), patients with complete gonadal dysgenesis (CGD; e.g. Swyer syndrome). WHAT IS KNOWN ALREADY: A GBY locus was proposed to be present on the human Y chromosome because only DSD patients with a Y chromosome in their karyotype have a high-although variable-risk (up to 55%) for germ cell tumour development. GBY was mapped to the proximal part of the short and long Y arm. TSPY located in the proximal part of the short Y arm (Yp11.1) was found to be a strong GBY candidate gene. It is expressed in the germ cells of DSD-XY patients with distinct etiologies but also in foetal and pre-meiotic male spermatogonia. However, the GBY region extends to proximal Yq11 and therefore includes probably more than one candidate gene. STUDY DESIGN, SIZE, DURATION: Protein expression of the putative GBY candidate gene in proximal Yq11, DDX3Y, is compared with that of TSPY in serial gonadal tissue sections of 40 DSD-XY individuals from the three DSD patient groups (MGD, Complete Androgen Insensitivity Syndrome [CAIS], CGD) with and without displaying malignancy. Expression of OCT3/4 in the same tissue samples marks the rate of pluripotent germ cells. PARTICIPANTS/MATERIALS, SETTING, METHOD: A total of 145 DSD individuals were analysed for the Y chromosome to select the DSD-XY subgroup. PCR multiplex assays with Y gene specific marker set score for putative microdeletions in GBY Locus. Immunohistochemical experiments with specific antisera mark expression of the GBY candidate proteins, DDX3Y, TSPY, in serial sections of the gonadal tissue samples; OCT3/4 expression analyses in parallel reveal the pluripotent germ cell fraction. MAIN RESULTS AND THE ROLE OF CHANCE: Similar DDX3Y and TSPY protein expression patterns were found in the germ cells of DSD-XY patients from each subgroup, independent of age. In CAIS patients OCT3/4 expression was often found only in a fraction of these germ cells. This suggest that GBY candidate proteins are also expressed in the non-malignant germ cells of DSD-XY individuals like in male spermatogonia. LIMITATIONS, REASONS FOR CAUTION: Variation of the expression profiles of GBY candidate genes in the germ cells of some DSD-XY individuals suggests distinct transcriptional and translational control mechanisms which are functioning during expression of these Y genes in the DSD-XY germ cells. Their proposed GBY tumour susceptibility function to transform these germ cells to pre-malignant GB/Germ Cell Neoplasia in Situ (GB/GCNIS) cells seems therefore to be limited and depending on their state of pluripotency. WIDER IMPLICATIONS OF THE FINDINGS: These experimental findings are of general importance for each individual identified in the clinic with DSD and a Y chromosome in the karyotype. To judge their risk of germ cell tumour development, OCT3/4 expression analyses on their gonadal tissue section is mandatory to reveal the fraction of germ cells still being pluripotent. Comparative expression analysis of the GBY candidate genes can be helpful to reveal the fraction of germ cells with genetically still activated Y chromosomes contributing to further development of malignancy if at high expression level. STUDY FUNDING/COMPETING INTEREST(S): This research project was supported by a grant (01GM0627) from the BMBF (Bundesministerium für Bildung und Forschung), Germany to P.H.V. and B.B. The authors have no competing interests.

Natural conception rates in subfertile couples following fertility awareness training.

PURPOSE: To analyze cumulative pregnancy rates of subfertile couples after fertility awareness training. METHODS: A prospective observational cohort study followed 187 subfertile women, who had received training in self-observation of the fertile phase of the menstrual cycle with the Sensiplan method, for 8 months. The women, aged 21-47 years, had attempted to become pregnant for 3.5 years on average (range 1-8 years) before study entry. Amenorrhea, known tubal occlusion and severe male factor had been excluded. An additional seven women, who had initially been recruited, became pregnant during the cycle immediately prior to Sensiplan training: this is taken to be the spontaneous pregnancy rate per cycle in the cohort in the absence of fertility awareness training. RESULTS: The cumulative pregnancy rate of subfertile couples after fertility awareness training was 38% (95% CI 27-49%; 58 pregnancies) after eight observation months, which is significantly higher than the estimated basic pregnancy rate of 21.6% in untrained couples in the same cohort. For couples who had been seeking to become pregnant for 1-2 years, the pregnancy rate increased to 56% after 8 months. A female age above 35 (cumulative pregnancy rate 25%, p = 0.06), couples who had attempted to become pregnant for more than 2 years (cumulative pregnancy rate 17%, p < 0.01), all significantly reduce the chances of conceiving naturally at some point. CONCLUSIONS: Training women to identify their fertile window in the menstrual cycle seems to be a reasonable first-line therapy in the management of subfertility.

Low androgen signaling rescues genome integrity with innate immune response by reducing fertility in humans.

Development of the gonads under complex androgen regulation is critical for germ cells specification. In this work we addressed the relationship between androgens and genomic integrity determining human fertility. We used different study groups: individuals with Differences of Sex Development (DSD), including Complete Androgen Insensitivity Syndrome (CAIS) due to mutated androgen receptor (AR), and men with idiopathic nonobstructive azoospermia. Both showed genome integrity status influenced by androgen signaling via innate immune response activation in blood and gonads. Whole proteome analysis connected low AR to interleukin-specific gene expression, while compromised genome stability and tumorigenesis were also supported by interferons. AR expression was associated with predominant DNA damage phenotype, that eliminated AR-positive Sertoli cells as the degeneration of gonads increased. Low AR contributed to resistance from the inhibition of DNA repair in primary leukocytes. Downregulation of androgen promoted apoptosis and specific innate immune response with higher susceptibility in cells carrying genomic instability.

[Contraception in adolescents]. / Empfängnisverhütung bei Jugendlichen.

PIP: In a study carried out in Germany between 1985-89 unintended pregnancy was found in 7.9% of girls aged 15-21 in 1985 and in 5.2% in 1989. A study of 2905 young people aged 14-18 in Austria indicated that 75% of girls and 55% of boys had sexual intercourse by age 18 making contraception vital for adolescents. Among oral contraceptives (OCs) micropills with 20 mcg ethinyl estradiol barely affect the follicle stimulating hormone (FSH) and luteinizing hormone (LH) levels, but the gestagen component can induce bleeding, spotting, and breast symptoms. Discontinuation quickly restores the normal connection of the hypophysis and ovary without affecting later pregnancy. 5.1 years after the end of high-dose combination OC use for 9-46 months only 3 out of 13 women did not become pregnant. OCs reduce bleeding disorders, anemia, and dysmenorrhea, ovarian cancer, and endometrial cancer. Their effect on breast cancer is not clear. Phenobarbital and rifampicin accelerate OC metabolism, and OCs reduce the effect of anticonvulsives and tolbutamide (for hypoglycemia). Neogynon and Stediril D are postcoital pills used within 48 hours of intercourse. IUDs are not recommended, as adnexal infection is 1.5-2 times higher in girls 14018 using IUDs. The effectiveness of the diaphragm and condom depend on motivation; creams and vaginal sponges are useful but they may cause irritation. The Billings method produced only a 2.9 Pearl-index reliability in 7000 cycles, thus natural methods often fail. Before age 14 girls must have parental consent for prescription of OCs, after 14 the physician is not liable for OC prescription, but induced abortion still requires parental consent until age 18.^ieng

The effectiveness of a fertility awareness based method to avoid pregnancy in relation to a couple's sexual behaviour during the fertile time: a prospective longitudinal study.

BACKGROUND: The efficacy of fertility awareness based (FAB) methods of family planning is critically reviewed. The objective was to investigate the efficacy and the acceptability of the symptothermal method (STM), an FAB method that uses two indicators of fertility, temperature and cervical secretions observation. This paper will recommend a more suitable approach to measure the efficacy. METHODS: Since 1985, an ongoing prospective observational longitudinal cohort study has been conducted in Germany. Women are asked to submit their menstrual cycle charts that record daily basal body temperature, cervical secretion observations and sexual behaviour. A cohort of 900 women contributed 17,638 cycles that met the inclusion criteria for the effectiveness study. The overall rates of unintended pregnancies and dropout rates have been estimated with survival curves according to the Kaplan-Meier method. In order to estimate the true method effectiveness, the pregnancy rates have been calculated in relation to sexual behaviour using the 'perfect/imperfect-use' model of Trussell and Grummer-Strawn. RESULTS: After 13 cycles, 1.8 per 100 women of the cohort experienced an unintended pregnancy; 9.2 per 100 women dropped out because of dissatisfaction with the method; the pregnancy rate was 0.6 per 100 women and per 13 cycles when there was no unprotected intercourse in the fertile time. CONCLUSIONS: The STM is a highly effective family planning method, provided the appropriate guidelines are consistently adhered to.

Definition and prevalence of subfertility and infertility.

A common definition of sub- and infertility is very important for the appropriate management of infertility. Subfertility generally describes any form of reduced fertility with prolonged time of unwanted non-conception. Infertility may be used synonymously with sterility with only sporadically occurring spontaneous pregnancies. The major factor affecting the individual spontaneous pregnancy prospect is the time of unwanted non-conception which determines the grading of subfertility. Most of the pregnancies occur in the first six cycles with intercourse in the fertile phase (80%). After that, serious subfertility must be assumed in every second couple (10%) although--after 12 unsuccessful cycles--untreated live birth rates among them will reach nearly 55% in the next 36 months. Thereafter (48 months), approximately 5% of the couples are definitive infertile with a nearly zero chance of becoming spontaneously pregnant in the future. With age, cumulative probabilities of conception decline because heterogeneity in fecundity increases due to a higher proportion of infertile couples. In truly fertile couples cumulative probabilities of conception are probably age independent. Under appropriate circumstances a basic infertility work-up after six unsuccessful cycles with fertility-focused intercourse will identify couples with significant infertility problems to avoid both infertility under- and over-treatment, regardless of age: Couples with a reasonably good prognosis (e.g. unexplained infertility) may be encouraged to wait because even with treatment they do not have a better chance of conceiving. The others may benefit from an early resort to assisted reproduction treatment.

Results of an efficacy-finding study (EFS) with the computer-thermometer Cyclotest 2 plus containing 207 cycles.

Prospectively collected cycles of 207 women were used to find out the efficacy of the Cyclotest 2 plus algorithm in detecting the fertile time in a woman's cycle. The results of the device were compared with the beginning and the end of the fertile time identified by the symptothermal method (STM) of natural family planning (NFP). It was found that the algorithm led to dangerous reduction of the fertile time (FT) in only 2 out of 207 woman cycles (0.96%). However, at the end of fertile time (FE) the device requested more abstinence than was necessary in about 12% of the cycles. We feel that more research should be performed on detecting the end of the fertile time.

Cycle characteristics after discontinuation of oral contraceptives.

Nearly 60% of the women between 20 and 40 years of age who do not want to conceive choose oral contraceptives (OCs) for contraception in Germany. In an ongoing prospective study on the use of natural family planning in Germany, 175 women have been observed for 3,048 cycles immediately after having discontinued OCs (post-pill group). They were compared to a control group of 284 women observed for 6,251 cycles, who had never taken OCs. Both groups were comparable in age and sociodemographic characteristics. After discontinuing OCs, 57.9% of all first cycles were ovulatory with sufficient luteal phases. However, for the total post-pill group the cycle length was significantly prolonged up to the ninth cycle. A significantly higher number of luteal phases were insufficient in the post-pill group. Major cycle disturbances (cycle length > 35 days or luteal phase of < 10 days of elevated basal body temperature or anovulatory cycles) were significantly more frequent in the post-pill group up to the seventh cycle. Cycle disturbances after discontinuing OCs were reversible but the time of regeneration took up to 9 months (significant) or even longer (not significant). These results will help to counsel couples who wish to conceive after discontinuing OCs or who want to continue contraception with alternative methods.

Research and quality control in natural family planning with relational database systems.

Research and quality control in natural family planning (NFP) is based on continuous data collection in prospective studies. The quality of the data is determined by the reliability of collection, input, management, and retrieval. During a period of ten years, different relational databases were programmed to manage the large number of very different data in NFP studies. Recently, all experience with different database systems has been summarized by writing and testing a completely new data management system based on MS Access 97: NFPDAT 1.0. This new software is used for data collection, evaluation and administration in NFP Study Groups. Over 200 internal formulae guarantee maximum data consistency while 30,000 cycles from 1477 patients were stored. Easy data evaluation for research and administration is possible with the help of a new report generator even without prior knowledge of SQL (System Query Language) or Visual Basic for MS Access 97. Using this method, interim results for research and quality control can be obtained at any time. NFPDAT can be used by all Natural Family Planning Study Groups using the symptothermal method for research and administration. With the help of NFPDAT, various prospective studies of Natural Family Planning were conducted.

Time to pregnancy: results of the German prospective study and impact on the management of infertility.

BACKGROUND: The likelihood of spontaneous conception in subsequent cycles is important for a balanced management of infertility. Previous studies on time to pregnancy are mostly retrospective and biased because of exclusion of truly infertile couples. The study aim was to present a non-parametric estimation of cumulative probabilities of conception (CPC) in natural family planning (NFP) users illustrating an ideal of human fertility potential. METHODS: A total of 346 women was observed who used NFP methods to conceive from their first cycle onwards. The couples practising NFP make optimal use of their fertility potential by timed intercourse. The CPC were estimated for the total group and for couples who finally conceived by calculating Kaplan-Meier survival rates. RESULTS: A total of 310 pregnancies occurred among the 346 women; the remaining 36 women (10.4%) did not conceive. Estimated CPC for the total group (n = 340 women) at one, three, six and 12 cycle(s) were 38, 68, 81 and 92% respectively. For those who finally conceived (truly fertile couples, n = 304 women), the respective pregnancy rates were 42, 75, 88 and 98% respectively. Although the numbers of couples in both groups were similar, the impact of age on time to conception, as judged by the Wilcoxon test, was less in the truly fertile than in the total group. CONCLUSIONS: Most couples conceive within six cycles with timed intercourse. Thereafter, every second couple is probably either subfertile or infertile. CPC decline with age because heterogeneity in fecundity increases. In the subgroup of truly fertile couples, an age-dependent decline in CPC is statistically less obvious because of high homogeneity, even with advancing age.

Retrospective clinical trial of contraceptive effectiveness of the electronic fertility indicator Ladycomp/Babycomp.

The Babycomp/Ladycomp (Valley Electronics Ltd., Eschenlohe, Germany) is an electronic device that combines the temperature method and calendar method for planning and preventing pregnancy by identifying the fertile and infertile phases of the menstrual cycle. In a retrospective clinical trial, the system was tested as a contraceptive aid. A total of 648 women from Germany and Switzerland have participated: 597 women with 10,275 months of use used the device for contraception. Thirty-three unplanned pregnancies were identified, giving a total pregnancy rate of 3.8 use effectiveness according to the Pearl Index. Six method-related pregnancies occurred, producing a method Pearl Index of 0.7. Calculating the cumulative pregnancy rates by life-table analysis, it was found that, after about one year of exposure, the probability of an unintended pregnancy was 5.3% (0.053), after 2 years it was 6.8% (0.068) and after about 3 years of exposure it was 8.2% (0.082). The mean length of the identified fertile period was 14.3 days with a standard deviation of 4.6 days in all cycles reported. The acceptance of the device by the woman and her partner was good. In fact, 21 of the 33 women who became pregnant would still recommend the device for further use (63.6%).

Sexual behavior of natural family planning users in Germany and its changes over time.

For 10 years, a prospective study has been taking place in Germany to examine the use of natural family planning (NFP). As natural methods are behavioral methods, use-effectiveness, acceptability and continuation rates are very much influenced by patterns of sexual behavior. Therefore we performed an analysis of the sexual behavior of NFP users. Out of the data base of 1211 clients and 12,591 cycles we could identify a group of 300 women, all NFP beginners, with 5900 contraceptive cycles, who contributed at least 12 cycles with reliable recording of their sexual activity. Different groups were analyzed with methods of analysis of variance and regression models to find out significant differences in their sexual behavior with respect to sociodemographic structure and time of use. Nearly half of all the women systematically combine the fertility awareness part of NFP with other family planning methods. They use barriers in more than 60% of their cycles. The other half never or only in about 7% of their cycles use additional barrier methods. The latter show a clear decrease in barrier use in the course of time, whereas the frequent barrier users constantly combine the advantages of two family planning methods. Regarding the frequency of intercourse they are the sexually more active ones and show distinct sociodemographic characteristics. We could confirm the existence of three groups of NFP users, which differ significantly in their use of NFP as a family planning method. Despite these differences the low pregnancy rates indicate the conscious and risk-related sexual behavior of the group members.

[How do self-observed cycle symptoms correlate with ovulation?]. / Wie korrelieren selbstbeobachtete Zyklussymptome mit der Ovulation?

The symptoms of self-observation of the menstrual cycle (basal body temperature, mucus symptom, autopalpation of the cervix) are often regarded as not reliable for ovulation detection. In a prospective study 87 NFP cycles are monitored additionally with ultrasound and LH tests to calculate the correlation of the ovulation-time with the symptoms of self-observation. Our results show that the symptoms of self-observation allow a reliable detection of the time of ovulation. Only a short introduction into the method of self-observation is a necessary precondition. The reliable detection of ovulation gives the opportunity of cycle analysis of large groups especially in long time investigations. In this way a large set of valuable and reliable data on normal and disturbed menstrual cycles will be available.

The CUE Fertility Monitor compared to ultrasound and LH peak measurements for fertile time ovulation detection.

A prospective study of the reliability of the CUE Fertility Monitor to identify the fertile time of the menstrual cycle was conducted. The device provides a digital measurement of the electrical resistance of saliva (SER) and vaginal secretions (VL). The readings of the device were compared with the fertile time detected by ultrasonography of the growing follicle and estimation of the LH surge to detect ovulation. Thirteen women participated in the study. Sixteen cycles contained both signals (SER, VL) for the beginning and the end of the fertile period. In 2 cycles a CUE signal could not be found by the device. Using a computerized algorithm for evaluation of the CUE signals, the beginning of the fertile period was accurately detected in 14 cycles; in 2 cycles the signal was found less than five days prior to ovulation. The last day of fertility was identified correctly by the CUE Fertility Monitor in 10 cycles; in 6 it was incorrectly identified during the time when the woman was still fertile. This suggests that the CUE Fertility Monitor utilizing the algorithm on which it currently is based cannot be recommended for natural family planning. However, we think that the algorithm for evaluation should be improved as useful signals in the menstrual cycle are detected.

[Results of a physician survey on the status of knowledge and attitude to natural family planning in West Germany 1988]. / Ergebnisse einer Arzte-Befragung über Kenntnisstand und Einstellung zur natürlichen Familienplanung in der Bundesrepublik Deutschland 1988.

Based on a questionnaire, reporters of the EMNID Poll Institute interviewed 229 general practitioners and 237 practising gynaecologists by telephone. When questioned which method for family planning was, in the physicians' opinion, most frequently used and which was most frequently recommended by physicians, contraceptive pills were far ahead of any other method. Somewhat surprising was the fact that up to 36% of the interviewed physicians considered that the intrauterine device is either the most frequently used or the most recommended method. Even the quantity of reports on condoms being the most frequently used method was relatively high (8-10%). 6% of the questioned physicians stated NFP methods as being mainly used, and 10% of the physicians recommended these methods. NFP methods also held the fourth place preceded by contraceptive pills, IUD and condom in the 1985 EMNID survey. Among the NFP methods, body basal temperature was reported to be the most popular and most frequently recommended method. The sympto-thermal method which is world-wide proposed as first choice by the experts, is still fairly unknown. The results arising from this survey indicate the necessity for physicians to gain a more thorough knowledge of modern NFP methods. Unjustified prejudices should be removed, the high reliability, which may be achieved at present, should be propagated and the undeniable advantages of NFP methods should be pointed out. The possible difficulties due to the necessary abstinence during the fertile period should, however, be kept in mind.

[Has family planning behavior in West Germany changed since 1985?]. / Hat sich das Familienplanungsverhalten in der BRD seit 1985 verändert?

A survey on the family planning behaviour in the Federal Republic of Germany was conducted by interviewers of the EMNID institute in 1985 (n = 1267) and 1989 (n = 950). The survey was carried out with women of 15 to 45 years of age. It was the aim of the 1989 study, to look into changes of the last four years generally and with regard to the increasing knowledge about AIDS. As the use of a combination of family planning methods has significantly increased in 1989, the overall percentage went very much beyond 100% (1985: 106.1% vs 1989: 138.5%). Hence, for comparison of the figures, we omitted any sociodemographic weighting. For each method, the percentage of the users is reported independently of any additional method used. The figures (%) for use of reversible methods of contraception 1985 vs 1989 were as follows: the pill (52.2/61.9), condom (10.0/24.8), IUD (14.1/10.8), withdrawal (5.8/6.6), mini-pill (1.7/6.5), NFP (8.8/6.0), locally applied chemical device (2.6/5.2), vaginal diaphragm (3.0/3.0). The frequency of sterilisation was 6.9 vs 5.7%; the frequency of unwanted pregnancies 26.6 vs 20.9%. 12.3% of the women aged 18-45 years stated, that family planning behaviour has changed in the last two years. 1/3 of these declared, that AIDS has played an important part in their decision. Answers to other questions are compared 1985 vs 1989, like "reasons for selecting a particular method", "need for use of contraceptives", "frequency of unwanted pregnancies" and "importance of natural methods".

Estimated maximum failure rates of cycle monitors using daily conception probabilities in the menstrual cycle.

BACKGROUND: A number of menstrual cycle monitors have been developed to detect the fertile window of the menstrual cycle, mainly for contraceptive purposes. Reliable data on most of these systems are still missing but are urgently needed because many women use them and the tested systems differ enormously in price and effectiveness. We suggest a new efficacy estimating method to evaluate cycle monitors prior to full prospective clinical trials. METHODS: Sixty-two women prospectively tested seven cycle monitors and the symptothermal method (STM) of natural family planning (NFP) but not more than two different systems at the same time. The clinical fertile window was determined by detecting the day of ovulation using daily urinary LH measurements and daily ultrasonic folliculometry. This was compared to the fertile phase predicted by the systems. Maximum failure rates were estimated for each cycle monitor and the STM, using the daily conception probability rates taken from the European Fecundability Study. Intercourse was assumed to occur on each of all falsely predicted days of infertility. RESULTS: Sixty-two women with a mean age of 31 years (range: 21-42 years) contributed a total of 122 cycles to this study. Monitors based on the microscopic evaluation of saliva or mucus had many more false infertile days than the other methods based on temperature or hormonal measurements (225 versus 42 days). The maximum unintended pregnancy rates per cycle for temperature computers were estimated to be 0.0134-0.0336, for the hormonal computer 0.1155 and for mini-microscopes 0.2313-0.2369. For the STM of NFP, there were no false infertile days. CONCLUSIONS: The STM of NFP proved to be the most effective contraceptive method to detect the fertile window among all the methods tested. The estimated efficacy of the other cycle monitors range from the temperature computers (upper level) to the hormonal computer (medium level) and the mini-microscopes with very low estimated contraceptive efficacy.

Natural family planning with and without barrier method use in the fertile phase: efficacy in relation to sexual behavior: a German prospective long-term study.

A large prospective long-term study with users of natural family planning (NFP) methods has been conducted to analyze the relation between unintended pregnancy rates and sexual behavior with special reference to barrier method use in the fertile phase. Seven hundred and fifty eight NFP beginners, 19-45 years of age, 14870 cycles, 28 unintended pregnancies were studied. Of the couples, 54.2% use NFP only or predominantly and 45.9% use mixed methods (additional barrier method use in the fertile phase in 55.7% of the cycles). The overall pregnancy rate after 12 cycles of exposure is 2.2% according to the actuarial method. There is no significant difference between NFP users and mixed methods users and also no significant effect of duration of use in the first 5 years of exposure. During "perfect use" the pregnancy rate at 12 months is 0.63%. When only protected intercourse takes place in the fertile phase the pregnancy rate is 0.45%. The symptothermal method of NFP is most unforgiving for imperfect use (unprotected intercourse in the fertile phase). However, it is extremely effective when either abstinence or protected intercourse is used in the fertile phase.

Effectiveness and acceptibility of the symptothermal method of natural family planning in Germany.

Throughout Germany, 851 women who were instructed in natural family planning participated in a prospective study. Of these, 255 women with 3174 cycles used only natural family planning for family planning and 274 women with 3995 cycles occasionally used barrier methods in the fertile phase. For natural family planning--only users, the Pearl rate for unplanned pregnancy was 2.3 and for mixed-method users 2.1. Most pregnancies resulted from unprotected intercourse during the fertile phase, and the use of barrier methods does not reduce risk-taking.