Effects of progestagens on follicular growth and oocyte developmental competence in FSH-treated ewes.
Berlinguer. F F; Gonzalez-Bulnes. A A; Succu. S S; Leoni. G G; Mossa. F F; Bebbere. D D; Ariznavarreta. C C; Tresguerres. J A F JA; Veiga-Lopez. A A; Naitana. S S
Key Findings
- Progestagen treatment did not alter follicle growth dynamics compared to controls.
- Estradiol concentrations were lower in progestagen‑treated ewes.
- Oocyte recovery rate dropped from 83% to 71% with progestagen.
- Cleavage rates after IVF fell dramatically (82.6% to 39.1%) in the progestagen group.
Practical Outcomes
- If you’re using FSH (Ovagen) for in‑vitro embryo production or similar protocols, avoid adding a progestagen beforehand, as it appears to reduce egg yield and early embryo development. The study mainly applies to sheep reproduction, so its direct relevance to human biohacking or longevity practices is limited.
Summary
In a study with sheep, giving a progesterone‑like drug (progestagen) before stimulating the ovaries with FSH (the Ovagen product) didn’t change how many follicles grew, but it lowered estrogen levels, reduced the number of eggs that could be collected, and cut the success of early embryo development. The findings suggest that the progestagen may hurt egg quality when used together with FSH.
Abstract
Previous research has reported evidence for negative effects of progestagens on follicular growth and oocyte competence. In the present study, negative effects of progestagens on follicular growth and oocyte developmental competence were assessed. During the breeding season, 20 Sarda ewes were treated with two doses of cloprostenol, 10 days apart, to assure the presence of a corpus luteum (CL). On day 5 after the second cloprostenol dose, 10 ewes were treated with a progestagen sponge while 10 females remained untreated. Starting on day 7 after the second cloprostenol dose, all the ewes were treated with 6 equal doses of 24 I.U. of FSH (Ovagen, ICP, NZ), every 12h. The number of follicles > or =2mm in diameter increased (P<0.0005) in all the ewes from 24 h before to 60 h after the first FSH dose (from 12.8+/-1.1 to 23.4+/-1.3 in treated and from 12+/-0.6 to 22+/-1.2 in untreated ewes, n.s.). There were no significant differences in follicle dynamics between groups, but concentrations of estradiol in control ewes were higher than in the progestagen group (P<0.05). Twelve hours after the last FSH dose, oocytes were collected by ovum pick-up. Recovery rates were lower for progestagen-treated ewes (71.1 versus 83%; P<0.001). After IVP procedure, cleavage rate was also lower in the progestagen group (39.1 versus 82.6%; P<0.001). Furthermore, blastocysts output revealed that oocyte developmental competence was lower in progestagen group (17.3 versus 30.4%; P=0.245), although differences were not significant. These results suggest deleterious effects from progestagen on oocyte developmental competence and set the basis for new protocols for in vitro embryo production.
Study Information
pubmed
2006
2006-05-02T00:00:00.000Z
10.1016/j.domaniend.2006.04.007