Human reproduction
About a once month, an ovum (egg) is released by the female’s ovary and sent down the fallopian tube and burrow into the egg, a process known as fertilization. This union forms a single cell called a zygote. The zygote then becomes implanted in the lining of the uterus. The uterus expands dramatically as the egg develops into an embryo and then a growing fetus. When the fetus is mature enough to survive outside of the womb, the cervix dilates, and contractions of the uterus propel the fetus through the birth canal.
Reproductive structures begin to form in the embryonic stage. By week 6, gonads and genitalia are present but undifferentiated. Whether the embryo becomes male or female is determined by one chromosome delivered by semen
Sex
The female egg contains one X sex chromosome, and the male sperm contains either one X or one Y sex chromosome. If the chromosome pair in the resulting zygote is XY, the gonads develop into testes starting in week 7. If the chromosome pair is XX, the gonads become ovaries starting in week 8. Testes secrete testosterone, forming male genitalia around week 10. Without testosterone, female genitalia form. All reproductive structures are in place at birth or shortly after. At puberty, an increase in sex hormones will grow them to their adult size and reproductive capability.
Gravida
Indicates the number of times the had been pregnant (current and past), regardless of the pregnancy outcomes
Para
Indicates the number of viable births. Pregnancies consisting of multiples, such as twins or triplets, count as ONE birth for the purpose of this notation
Abortus
The number of pregnancies that were lost for any reason, including included abortions or miscarriage. The abortus term is not used when no pregnancies have been lost
G3P3
A woman who has had three pregnancies, all of which resulted in live births
G3P2A1
A woman who has had three pregnancies, one of which was an abortion
G2P0A2
A woman who has had two pregnancies, both of which resulted in miscarriages
GTPAL
An acronym used in obstetrics and gynecology to provide a comprehensive summary of a woman’s obstetrics history during pregnancy. G-gravida, T-number of term deliveries P- pregnancy outcomes, A- number of abortions, miscarriages, or ectopic pregnancies L- number of living children