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Related to gestation: culdoscope, Fetal development


the period of development of the young in viviparous animals, from the time of fertilization of the oocyte (ovum) to birth; see also pregnancy.
gestation period the duration of pregnancy; in the human female, the average length, calculated from the first day of the last normal menstrual period, is 280 days, or 6 lunar months. The normal limits of the human gestation period are from 37 weeks (259 days) to 42 weeks (293 days); days and weeks are counted as completed days and weeks. If one counts from the moment of conception, the length of time is 266 days (280−14 days).




The state of a female after conception and until the termination of the gestation.
[L. praegnans (praegnant-), pregnant, fr. prae, before, + gnascor, pp. natus, to be born]


/ges·ta·tion/ (jes-ta´shun) pregnancy. See also gestation period, under period. gesta´tional


The period of development in the uterus from conception until birth; pregnancy.

ges′ta·to′ry (jĕs′tə-tôr′ē), ges·ta′tion·al adj.


Etymology: L, gestare, to bear
in a viviparous animal, the period from the fertilization of the ovum until birth. Gestation varies with the species. In humans the average duration is 266 days, or approximately 280 days from the onset of the last menstrual period. A gestation time of less than 37 weeks is regarded as premature; one that continues beyond 42 weeks is considered postmature, regardless of the size of the fetus or other factors. See also pregnancy.


Pregnancy Reproduction medicine The period from fertilization to delivery/birth. See Multiple gestation.


The state of a female after conception and until the termination of the gestation.
Synonym(s): gestation.
[L. praegnans (praegnant-), pregnant, fr. prae, before, + gnascor, pp. natus, to be born]


the development of the embryo in the uterus of mammals. The gestation period is the time elapsing from fertilization and the implantation of the embryo to birth. This takes 60 days in the domestic cat, 9 months in humans and 18 months in the Indian elephant.


The period from conception to birth, during which the developing fetus is carried in the uterus.
Mentioned in: Childbirth


n the period of time between the fertilization of a mam-mal's egg until the time it is born.


State of a female after conception and until termination of gestation.
[L. praegnans (praegnant-), pregnant, fr. prae, before, + gnascor, pp. natus, to be born]


the period of development of the young in viviparous animals, from the time of fertilization of the ovum to birth. See also pregnancy.

gestation period
the duration of pregnancy in the domestic animal species are: cow—273 to 292 days (Bos taurus), 271 to 310 days (Bos indicus); mare—333 to 346 days; ass—365 to 375 days; ewe—143 to 147 days (meat sheep), 147 to 155 days (merino); goat doe—146 to 155 days; sow—111 to 116 days; bitch—58 to 68 days; queen—61 to 70 days.
In laboratory and quasi-pet animals: guinea pig 59-72 days, gerbil 24-26 days, hamster 15.5-16 days, mouse 19-21 days, rat 21-23 days, rabbit 29-35 days.
perpetual gestation chart
a table based on the average gestation period of the particular species, e.g. 63 days for bitches, that plots the anticipated date of parturition against the breeding (conception) date. Designed to be independent of the year so it is valid indefinitely.
prolonged gestation

Patient discussion about gestation

Q. Will she be tired all her pregnancy? My wife is 6 weeks pregnant with our first baby. She is tired all the time and goes to bed at 7 PM. Will she be like this the whole pregnancy?

A. Don't worry, this is very common! Here are some tips to help her with her tiredness:
-She should take short breaks during the day and lie down and lift her feet up. This can help her feel better and less tired. If she is at work and can't lie down, then she should just pick her legs up on a chair.
-She should take a few short naps during the day and sleep at least 7-8 hours a night.
- She should sleep on her left side as this improves the blood flow to the womb.

Q. Is this the symptom of pregnancy? I have burning rashes all over my face and neck and it is itching a lot. I’ve tried with popular brand lotions and all of them are in vain. I have consulted skin specialist also and he said this is not an allergic reaction. Can anyone give me some insight on this and what I could use to get rid of this crazy outbreak of rashes every now and then….. It’s just my skin got really sensitive for some reason... Is this the symptom of pregnancy?

A. I really doubt this. Morning sickness is one of the primary symptoms of pregnancy and you didn’t say anything about it. But developing rashes might be due to any skin deficiency for which you may have to consult a physician than forming your own conclusions. I don't know about the rash, but I broke out a lot during my first pregnancy. It's not a sure sign, but possible. My skin was itchy everywhere when I was pregnant. Every woman is different, some break out with bad acne when they get pregnant, and other's clear up. I broke out bad, but if you know your body, then it could be a sign!

Q. Which vaccinations are allowed during pregnancy? I'm 13 weeks pregnant and planning to travel to east Africa.

A. if you have to make some "vaccinations" to travel outbroad, you can also find out if a homeopathic vaccination exists. this will be okay for you and for sure.

Please check urgently the links on this page before you would like to go on with any vaccination, you should check out this very long list of links:

at the bottom you will also find links in english. vaccinations in general are very disputable/dubious and it is probably time that we learn about it.

More discussions about gestation
References in periodicals archive ?
Maternal stress during gestation causes numerous effects on infant physiology that extend well into adulthood.
All fetuses had confirmed gestational age dating in the first trimester and normal anatomy at 18–20 weeks of gestation by ultrasound examination.
A single course of betamethasone is recommended for pregnant women between 34 0/7 and 36 6/7 weeks of gestation at risk of preterm birth within 7 days, and who have not received a previous course of antenatal corticosteroids.
Stillbirths were defined as intrauterine foetal death between 25 weeks gestation and delivery.
Ectopic gestation is a commonly seen acute abdominal disease and also a cause for the death of pregnant women.
For each time point (parity), we used the Cochran-Armitage test to examine the association of sow cumulative culling rate with body weight at d 109 of gestation of parity 1.
Gestational age was calculated from Last Menstrual Period (LMP), if she had regular menstrual cycle in the past three months; but women with irregular menstrual cycle, first trimester ultrasonography Biometry was compared with second trimester ultrasonography Biometry and if there was less than two weeks' difference in gestation was considered for the study.
After 25 weeks' gestation, statistically significant differences in head circumference emerged, and at 35 weeks, median head circumference was 320 em in whites, 317 em in Hispanics, 316 em in Asians, and 314 em in African Americans, she said.
Pregnant animals were euthanized using ether on the day 16 or the day 19 of gestation.
Results: Women in the DHA supplementation group reported lower levels of perceived stress at 30 weeks of gestation, controlling for depression and negative life events (mean 27.