Spontaneous Conception
Medically unassisted human conception includes the following steps:
- Ovulation
Approximately fourteen days prior to the beginning of a menstrual period, an ovarian follicle releases a microscopic egg (ovulation). Shortly after ovulation, the egg is captured by one of the Fallopian tubes and brought inside the tube.
- Fertilization
Sperm, which can wait in the Fallopian tubes for several days after intercourse or artificial insemination, must fertilize the egg within 12 to 16 hours of ovulation.
- Early embryonic development
The fertilized egg (embryo) moves through the Fallopian tube and starts to divide the day after fertilization. In two days, it has 4 cells, in three days, 8 cells, and in six days it has over 100 cells (blastocyst).
- Endometrial lining
The female hormones estradiol (estrogen, E2) and progesterone, produced by the ovulating follicle, prepare the lining of the uterus for implantation.
- Implantation
Five to seven days after ovulation, the embryo hatches out of its egg shell, implants into the lining of the uterus and starts to produce the pregnancy hormone Human Chorionic Gonadotropin (HCG). HCG can be detected with a blood pregnancy test approximately 9 to 10 days after ovulation. A urine pregnancy test will typically turn positive approximately two weeks after ovulation.
If you have any questions regarding the process of conception, please contact us by phone at 650-322-0500 or via email at care@BayIVF.com. To request an appointment, please go to the Request an Appointment page.
