| pubmed-article:10950454 | pubmed:abstractText | Twenty early pregnancies were diagnosed and monitored in vervet monkeys by ultrasonography. Non-gravid uteri became increasingly echogenic from cycle days 7 to 26. The first definite sign of pregnancy was a gestational cavity of 2 mm (+/- 0.80) at 33.0 (+/- 1.48) days menstrual age, which was also used to date all subsequent features. Earlier signs, such as an endometrial line swelling or endometrial 'pregnancy' ring, as reported for other non-human primate species, could not be reliably and consistently used to diagnose pregnancy in vervet monkeys. A rapid increase of the gestational cavity size from days 37 to 49 corresponded closely to a rapid increase in plasma progesterone concentration from day 39 to 49. The first yolk sac was recognizable at 38.0 days (+/- 3.10) and measured 3.3 mm (+/- 0.40) in diameter. A heart beat could be detected at 45.5 (+/- 1.73) days and the size of the first measurable embryo at 35 days was 2 mm. The dating of most features was within the range reported for other non-human primate species. | lld:pubmed |
