The genotype of the mother and the fetus influences the efficacy of a teratogen. For example, genotype determines the prevalence of cleft palate in inbred strains of mice whose mothers are administered cortisol during pregnancy.
Most women will not start ovulating in the first six weeks after giving birth.1 Breastfeeding typically delays the onset of ovulation.2 Depending on the intensity of breastfeeding, it can be several months or over a year before you regain your fertility.
One of your ovaries will release an egg (ovulation) about 12 to 14 days before your period starts. The first day of your period, when you start bleeding, is counted as the first day of your cycle. If you have a 28-day cycle, you'll usually ovulate some time between day 12 and day 16 of your cycle.During your period an egg is usually developing, ready for release mid-cycle. The time it takes for an egg to mature within the ovary can vary. This means that the day you ovulate can also vary from cycle to cycle.If your cycle is short, 22 days for example, then you could ovulate just days after your period, if your period lasted seven days.The longest that sperm can survive in fertile cervical mucus is seven days. So it may just be possible for you to get pregnant if you ovulate a little earlier than usual.he time it takes for an egg to mature within the ovary can vary. This means that the day you ovulate can also vary from cycle to cycle. If your cycle is short, 22 days for example, then you could ovulate just days after your period, if your period lasted seven days.