Unusual Twinning Resulting in Chimerism: A Systematic Review on Monochorionic Dizygotic Twins.

Traditionally, it is understood that dizygotic (DZ) twins always have a dichorionic placenta. However, with 8% blood chimerism in DZ twins, placental sharing is probably more common than previously has been recognized. In this article, we will review all available cases of monochorionic dizygotic (MCDZ) twins. A total of 31 twins have been described in literature. A monochorionic diamniotic placenta is reported in all cases. Assisted reproductive technology is responsible for the origin of the pregnancy in 82.1% of the cases. In 15.4% of the sex-discordant twins, a genital anomaly was reported in one of the twins. Chimerism is demonstrable in 90.3% of the twins, leading to various diagnostic difficulties. As this review shows that most MCDZ twins are discovered by accident, it can be argued that it is far more common than has been assumed until now. However, the prevalence is still unclear. Awareness of MCDZ twinning is important, with subsequently correct medical strategies. Similarly, the resulting (blood) chimerism is essential to consider in diagnostic procedures, pre- and postnatally. More research on the effect of placental transfusion between sex-discordant twins is required.

Ovarian reserve and anti-Mullerian hormone (AMH) in mothers of dizygotic twins.

This study aimed to explore if natural dizygotic (DZ) twinning is associated with earlier menopause and lower anti-Mullerian hormone (AMH) values. We investigated if advanced biological reproductive aging, which can be responsible for the multiple follicle growth in familial twinning, is similar to mechanisms that occur in normal ovarian aging, reflected by earlier menopause in mothers of DZ twins and lower levels of AMH. A total of 16 mothers of DZ twins enrolled with the Netherlands Twin Register (average age at first assessment: 35.9 ± 3.0 years) and 14 control mothers (35.1 ± 3 years) took part in a prospective study. Fifteen years after entry into the study, which included follicle-stimulating hormone (FSH) assessment, AMH was measured in stored serum samples and menopause status was evaluated. Average AMH levels were not significantly different between DZ twin mothers and controls (2.1 ± 2.4 µg/L vs. 1.9 ± 1.9 µg/L). Among the 16 mothers of twins, 7 had an elevated (FSH) value over 10 U/L at first assessment. Their AMH levels were lower than the nine twin mothers with normal FSH values: 0.6 ± 0.4 versus 3.4 ± 2.6 µg/L (p = .01). Of the mothers of twins, eight mothers had entered menopause at the second assessment compared with only one control mother (p = .07). Thus, slightly more DZ mothers were in menopause than the control mothers, although this difference was not significant. The subgroup of DZ twin mothers who had an increased FSH concentration 15 years ago had a limited ovarian reserve as reflected by lower AMH levels. These data indicate that advanced ovarian aging can be a feature in familial DZ twinning, particularly with elevated early follicular phase FSH.

First-line ovulation induction for polycystic ovary syndrome: an individual participant data meta-analysis.

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most frequent cause of anovulatory infertility. In women with PCOS, effective ovulation induction serves as an important first-line treatment for anovulatory infertility. Individual participant data (IPD) meta-analysis is considered as the gold standard for evidence synthesis which provides accurate assessments of outcomes from primary randomised controlled trials (RCTs) and allows additional analyses for time-to-event outcomes. It also facilitates treatment-covariate interaction analyses and therefore offers an opportunity for personalised medicine. OBJECTIVE AND RATIONALE: We aimed to evaluate the effectiveness of different ovulation induction agents, in particular letrozole alone and clomiphene citrate (CC) plus metformin, as compared to CC alone, as the first-line choice for ovulation induction in women with PCOS and infertility, and to explore interactions between treatment and participant-level baseline characteristics. SEARCH METHODS: We searched electronic databases including MEDLINE, EMBASE and Cochrane Central Register of Controlled Trials up to 20 December 2018. We included RCTs comparing the following interventions with each other or placebo/no treatment in women with PCOS and infertility: CC, metformin, CC plus metformin, letrozole, gonadotrophin and tamoxifen. We excluded studies on treatment-resistant women. The primary outcome was live birth. We contacted the investigators of eligible RCTs to share the IPD and performed IPD meta-analyses. We assessed the risk of bias by using the Cochrane risk of bias tool for RCTs. OUTCOMES: IPD of 20 RCTs including 3962 women with PCOS were obtained. Six RCTs compared letrozole and CC in 1284 women. Compared with CC, letrozole improved live birth rates (3 RCTs, 1043 women, risk ratio [RR] 1.43, 95% confidence interval [CI] 1.17-1.75, moderate-certainty evidence) and clinical pregnancy rates (6 RCTs, 1284 women, RR 1.45, 95% CI 1.23-1.70, moderate-certainty evidence) and reduced time-to-pregnancy (6 RCTs, 1235 women, hazard ratio [HR] 1.72, 95% CI 1.38-2.15, moderate-certainty evidence). Meta-analyses of effect modifications showed a positive interaction between baseline serum total testosterone levels and treatment effects on live birth (interaction RR 1.29, 95% CI 1.01-1.65). Eight RCTs compared CC plus metformin to CC alone in 1039 women. Compared with CC alone, CC plus metformin might improve clinical pregnancy rates (8 RCTs, 1039 women, RR 1.18, 95% CI 1.00-1.39, low-certainty evidence) and might reduce time-to-pregnancy (7 RCTs, 898 women, HR 1.25, 95% CI 1.00-1.57, low-certainty evidence), but there was insufficient evidence of a difference on live birth rates (5 RCTs, 907 women, RR 1.08, 95% CI 0.87-1.35, low-certainty evidence). Meta-analyses of effect modifications showed a positive interaction between baseline insulin levels and treatment effects on live birth in the comparison between CC plus metformin and CC (interaction RR 1.03, 95% CI 1.01-1.06). WIDER IMPLICATIONS: In women with PCOS, letrozole improves live birth and clinical pregnancy rates and reduces time-to-pregnancy compared to CC and therefore can be recommended as the preferred first-line treatment for women with PCOS and infertility. CC plus metformin may increase clinical pregnancy and may reduce time-to-pregnancy compared to CC alone, while there is insufficient evidence of a difference on live birth. Treatment effects of letrozole are influenced by baseline serum levels of total testosterone, while those of CC plus metformin are affected by baseline serum levels of insulin. These interactions between treatments and biomarkers on hyperandrogenaemia and insulin resistance provide further insights into a personalised approach for the management of anovulatory infertility related to PCOS.

Follicle-stimulating hormone receptor polymorphism affects the outcome of ovulation induction in normogonadotropic (World Health Organization class 2) anovulatory subfertility.

OBJECTIVE: To assess whether an FSH receptor polymorphism (Asn680Ser, rs6166) can affect the outcome of ovulation induction in normogonadotropic (World Health Organization class 2 [WHO2]) anovulatory subfertile women. DESIGN: Prospective, longitudinal, cohort study. SETTING: University-based fertility unit. PATIENT(S): A total of 240 consecutive women diagnosed with WHO2 anovulatory subfertility who underwent ovulation induction therapy. Results were replicated in a retrospective cohort of 185 patients with polycystic ovary syndrome (PCOS) (Rotterdam criteria). INTERVENTION(S): Ovulation induction using clomiphene citrate (CC) as first-line and exogenous gonadotropins (exFSH) as second-line therapy. MAIN OUTCOME MEASURE(S): Clomiphene-resistant anovulation (CRA), clomiphene failure (CCF), and ongoing pregnancy rate. RESULT(S): Genotyped patients (n = 159) were similar to nongenotyped women (n = 81) regarding clinical characteristics and outcomes of ovulation induction. The 680(Ser) allele was associated with CRA. A pooled analysis of both cohorts showed an 89% higher chance of CRA after CC treatment (odds ratio 1.9 [95% confidence interval 1.1-3.3]) in homozygous carriers of the FSH receptor variant (680(Ser/Ser)). A lower chance of ongoing pregnancy (hazard ratio 0.51 [95% confidence interval 0.27-0.98]) was observed among these patients during CC treatment in the prospective cohort. CONCLUSION(S): An FSH receptor polymorphism is associated with CRA during treatment with clomiphene citrate. These data may be used to design a treatment algorithm that is more efficacious and better tailored to the individual patient.

Early menopause in mothers of children with Down syndrome?

OBJECTIVE: To investigate whether having a Down syndrome pregnancy at a relatively young age is associated with lower ovarian reserve as reflected by lower antimüllerian hormone (AMH) levels and the occurrence of earlier menopause. DESIGN: Retrospective, case control study. SETTING: Not applicable. PATIENT(S): Two hundred twenty mothers (118 trisomy cases, 102 controls). INTERVENTION(S): Questionnaire and serum AMH measurement. MAIN OUTCOME MEASURE(S): Serum AMH levels and menopause, defined as not having a menstrual cycle for at least 1 year. RESULT(S): The participant response rate was 93%. After applying the exclusion criteria, 144 women were evaluable (73 trisomy cases, and 71 controls). The baseline characteristics of the women were not statistically significantly different. More women with a Down syndrome pregnancy had an AMH level below 0.5 µg/L, a difference that was statistically significant. Eleven women (15.1%) in the Down syndrome group had reached menopause compared with 9 (12.7%) of the controls. CONCLUSION(S): Women who have had a Down syndrome pregnancy at a younger age show signs of limited ovarian reserve, as evidenced by their frequently having lower AMH levels. The study has found no obvious signs of early menopause thus far. Whether their age at menopause is within the normal range remains to be determined.

Couples with unexplained subfertility and unfavorable prognosis: a randomized pilot trial comparing the effectiveness of in vitro fertilization with elective single embryo transfer versus intrauterine insemination with controlled ovarian stimulation.

OBJECTIVE: To evaluate the effectiveness of IVF with elective single embryo transfer (IVF-eSET) vs. IUI with controlled ovarian stimulation (IUI-COS) as an alternative treatment to reduce the risk for a multiple pregnancy. DESIGN: Randomized pilot trial. SETTING: Three academic and six teaching hospitals in the Netherlands. PATIENT(S): Couples with unexplained or mild male subfertility and an unfavorable prognosis for natural conception. INTERVENTION(S): One cycle of IVF-eSET or three cycles of IUI-COS. MAIN OUTCOME MEASURE(S): Ongoing pregnancy per couple. RESULT(S): We randomly allocated 116 women to IVF-eSET (n = 58) or IUI-COH (n = 58). There were 14 ongoing pregnancies (24%) in the IVF-eSET group and 12 pregnancies (21%) in the IUI-COS group (relative ratio 1.17; 95% confidence interval 0.60-2.30). There were two twin pregnancies in the IVF-eSET group (14%) and two twin pregnancies and one triplet pregnancy in the IUI-COH group (25%). CONCLUSION(S): In patients with unexplained or mild male subfertility and a poor prognosis for natural conception, one cycle of IVF-eSET might be as effective as three cycles of IUI-COS as primary treatment. Elective single embryo transfer does not seem an effective strategy in preventing multiple pregnancies in this particular population. In the future a strict SET policy (i.e., compulsory SET) might be an option. Our trial provides evidence for the feasibility and highlights the importance of a large definitive trial to determine the effectiveness and side effects of both strategies.