A review of the effectiveness of a progestogen-only pill containing norgestrel 75 µg/day.

OBJECTIVES: To review published data on the effectiveness of a progestogen-only pill containing norgestrel 75 µg/day which should be under consideration by the FDA in 2022 for sale over the counter in the US. STUDY DESIGN: A literature search in MEDLINE, EMBASE, and COCHRANE REVIEWS using specified search terms and adding related cross-references. RESULTS: We identified a total of thirteen relevant studies of women using norgestrel 75 µg/day. None were reported with the rigor characteristic of trial reporting today. Nevertheless, six studies provided data on 3,184 women who were not breastfeeding, followed for over 35,000 months and reported a range of overall failure rates during typical use of norgestrel 75 µg/day from 0 to 2.4/hundred woman-years giving an aggregate Pearl Index of 2.2. Seven additional studies involved 5,445 women some of whom were breastfeeding for at least part of the period of follow-up. More than 36,000 months of use yielded 12-month life table cumulative pregnancy rates for norgestrel 75 µg/day ranging from 0 to 3.4. We were unable to calculate an aggregate Pearl Index for the breastfeeding studies because of lack of crucial data. CONCLUSIONS: The data support that norgestrel 75 µg/day is highly effective in clinical use, with similar estimates of failure in breastfeeding and non-breastfeeding women, providing support to the case for approval without the need to see a healthcare provider.

Building proteomic pathways using Drosophila ventral furrow formation as a model.

Ventral furrow formation is the first morphogenetic movement to occur during Drosophila gastrulation causing the internalization of mesodermal precursors. A previous proteomic screen for ventral-specific proteome changes identified a set of about forty "difference-proteins" that spanned many cellular functions. To understand the connections between these disparate proteins, we initiated a pathway-building scheme using cycles of protein expression manipulation and proteome analysis. This pathway-building exercise started with the proteasomal subunit, Pros35, one of three proteasome subunits found to be ventral-specific difference-proteins. Here we show that Pros35 is a key regulator in ventral furrow formation. Altering the level of Pros35 led to ventral furrow defects. Proteome analysis of the changes induced by Pros35 RNAi showed extensive overlap with the original set of ventral-specific difference-proteins. One of the most prominent changes was in the extracellular iron carrier, Transferrin (Tsf1). Tsf1 is normally less abundant in ventral cells relative to lateral cells; however, RNAi of Pros35 in ventralized embryos negated this ventral-specific difference. Increasing Tsf1 in wild-type embryos blocked ventral furrow formation and caused proteome changes that were similar to the previously seen ventral-specific difference-proteins, including Pros35, which indicates the existence of an unprecedented regulatory loop between the proteasome and iron homeostasis. Additionally, we show that the iron regulatory protein, Irp-1A, also plays an important role in ventral furrow formation. Together these three proteins are part of a regulatory loop that coordinately controls a large number of ventral-specific protein changes.