Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [pregnancy]

The period after fertilization during which offspring develop within the body of a parent.

1
vote
2answers
80 views

Has an ectopic pregnancy's blastocyst ever been made to implant?

Has an ectopic pregnancy's blastocyst ever been successfully extracted from the Fallopian tube and made to implant in the uterus?
0
votes
2answers
145 views

In men, why do over 80% of sperm have abnormal form? [duplicate]

Here is the percentage of normal forms among fertile mens according to the centile (Source: Cooper et al. 2010): 2.5: 3% 5 (below this is Teratozoospermia): 4% 10: 5.5% 25: 9% 50 (median): 15% 75: ...
0
votes
0answers
43 views

What is the earliest point at which one can detect pregnancy?

Imagine a woman gets pregnant on day X. What is the shortest interval (like a day, a week, a month) after which she can detect she is pregnant? Example: Let's say that she keeps track of her ...
33
votes
6answers
12k views

Biological siblings possible with <9 months age difference?

I'm currently in the middle of writing a story, and one of the story elements threw up a question for me. In this story, there are two siblings, who are only one or two months apart in age. As they ...
1
vote
0answers
37 views

biological difference between 9 month and 7 month pregnanted humans [closed]

it possible baby born when 7 month of pregnancy, and possible when 9 month pregnancy. what happen in additional 2 month? what their difference. do they have different something.
1
vote
1answer
33 views

Why placental progesterone suppressed or drop before onset of labour?

As we know during pregnancy predominant hormone is progesterone which is at early pregnancy about first 3-4 months produce by corpus luteum of pregnancy together with estrogen after that placenta can ...
1
vote
0answers
22 views

How do (commensal and mutualist) microorganisms colonize the seminal vesicles?

Human's seminal fluid has it's own microbiome (Javurek et al. 2016). How do species of this microbiome (bacteria and eukaryotes) colonize the seminal vesicles? It is possible that different species ...
2
votes
0answers
39 views

What are limitations of giving birth to a baby from a frozen embryo?

Recently the story of a woman giving birth to baby girl from an embryo frozen 24 years ago hit the news. After an in vitro fertilization the embryo was frozen on 14 October 1992( Article in the ...
0
votes
1answer
30 views

Oocyte cryopreservation: genes from three parents?

Recently, I've heard of something called Oocyte cryopreservation, where a (fertilized, I think) egg from a woman is extracted, frozen and later thawed and reinserted into the woman to delay pregnancy. ...
27
votes
2answers
7k views

Where does my extra blood volume go after giving birth?

I'm pregnant. I've learnt that during my pregnancy my blood volume will increase by 50%. https://www.ncbi.nlm.nih.gov/m/pubmed/4075604/ So I'm wondering, what does my body do to decrease my blood ...
2
votes
1answer
174 views

Is it possible to become pregnant indirectly? [closed]

Is it possible to become pregnant indirectly? For instance, if there is some wet semen left behind inside tight clothing, jeans for example, and a woman tries them on for a couple of minutes? What is ...
11
votes
1answer
1k views

Has the gestation (pregnancy) period for humans always been 9 months?

At this point in our evolutionary progress, the expected human gestation period is (roughly) nine months long. My question is, has this duration of time always been the same for homo sapiens? Or, are ...
0
votes
1answer
123 views

Do human women smell different before they enter labour?

Surfing youtube I found a video where a cat shows a protective behaviour towards a pregnant woman soon to enter labour. In the miriad of average (dumb) comments I found another person stating that ...
2
votes
0answers
126 views

Can a mother somehow positively affect fetus during pregnancy?

My mother keeps telling me that I like to study and have a predisposition to it because she was a student when she was pregnant. I highly doubt it, because I can't find any logic in these words. I ...
1
vote
1answer
65 views

Is it possible to Breed an Animal to have more Females than Males?

Minute Earth talked about environmental factors that cause animals and humans to have more male or female children: https://www.youtube.com/watch?v=3IaYhG11ckA Presuming that is accurate, I was ...
1
vote
1answer
227 views

What evolutionary reason is there for hemolytic disease?

Nowawadays we have methods which allow us to overcome hemolytic disease of newborn or to prevent it to onset. The Rh or Kell conflict, but how is it possible that it is present? Why it haven't ...
1
vote
1answer
41 views

Which variables are controlled in the mammalian womb to ensure a healthy environment?

Recently, researchers have had some success with artificial wombs. Which aspects of the womb are difficult to replicate through technology?
2
votes
1answer
198 views

Gestation period of African savanna elephants?

I found out it is 22 months for African bush elephants, but is this also true for African savanna elephants?
1
vote
2answers
1k views

Do pregnancy and breast feeding increase basal metabolic rate?

Since pregnant or breastfeeding women have extra nutritional needs, does that mean they have a higher BMR? Why I thought the conclusion would be sensible: Since BMR is the energy needed to perform ...
9
votes
1answer
2k views

Can only fully matured sperm fertilize an egg?

Are only mature sperm able to fertilize an egg? If so, is there typically a reserve of mature sperm that are saved after an ejaculation or does a male need to wait for new sperm to mature before ...
5
votes
2answers
1k views

Could a man be proved positive for a pregnancy test?

From the question: Could a man be proved positive for a pregnancy test?. I don't mean if a man could be pregnant but if he runs a pregnancy test, it is possible for it to come out positive?
1
vote
0answers
228 views

What types of species can produce genetically identical offspring? [closed]

Talking about identical twins, triplets, etc. I'm curious which types of species are able produce genetically identical offspring. Let's limit the scope to species that reproduce sexually and ...
-2
votes
1answer
93 views

Are women smaller to optimize cloth needs during pregnancy? [closed]

Current life events made me wonder: Is it possible that female humans evolved to be on average smaller than males, so that they can reuse their partner's cloth during pregnancy? At least in my ...
5
votes
1answer
980 views

What happens if there is a blood incompatibility during pregnancy?

There are possible combinations of blood types with the rH factors: Rh factors are genetically determined. A baby may have the blood type and Rh factor of either parent, or a combination of both ...
4
votes
1answer
733 views

Could a trans-female person ever become pregnant?

I was told that a transgender person, which I will define as anyone assigned male or female at birth that identifies opposite to that assignment, could never become pregnant conceptually, due to the ...
1
vote
0answers
227 views

Zygote Implantation and Pregnancy Detection

In a normal pregnancy, the embryo (blastocyst) implants between 8-9 days after ovulation. My understanding is that it is able to implant because the fertilized embryo produces a hormone that triggers ...
4
votes
1answer
265 views

How to know the gestation time of pregnant mice?

In lab mice I wish to establish how many weeks my animals are into their pregnancy. Is there some way?
5
votes
1answer
19k views

How late in a human pregnancy can a zygote split?

This page indicates that the first two days is "very early" for a zygote to split, and that conjoined twins are the result of an "extremely late" split: If the zygote splits very early (in the ...
5
votes
1answer
260 views

Lack of A/B-antigen equivalent to Rhesus disease

Rhesus disease occurs when an Rh- mother is exposed to Rh antigens (often due to blood contact with an Rh+ child during delivery) and mounts an immune response which eventually results in the ...
1
vote
1answer
1k views

What leads to the different types of navels?

Obviously, there are "innies" and "outies" in the human belly button world. Both are the result of a knot tied in the umbilical cord just after birth. But why do some belly buttons become outies ...
3
votes
1answer
844 views

Why is the administration of exogenous Anti-D not harmful to the foetus?

Haemolytic disease of the newborn can result from Rhesus incompatibility in utero. In this disease a Rh-ve mother becomes exposed to the antigens of a Rh+ve foetus by fetomaternal haemorrhage causing ...
9
votes
1answer
11k views

What is the maximum number of babies a human woman can have?

I know you could divide the female fertility period (~40 years, right?) by 9 months which would give something like ~50 kids (with no multiple kids per pregnancy). The limiting factor in this ...
4
votes
1answer
765 views

What happens to the umblical cord inside the mother?

After giving birth to a child, the umblical cord is cut (and stored if they want). The end connected to the child's navel will fell off eventually but what happens to the end inside the mother? Will ...
1
vote
1answer
325 views

Why does an complete molar pregnancy not result in a clone?

Complete molar pregnancy is one where an ovum devoid of nucleus is fertilized by a sperm after which the haploid set of chromosomes double to form a diploid set. As far as my understanding extends if ...
0
votes
1answer
573 views

Can cfDNA testing distinguish results in the case of twins?

A fetus can now be screened for some of the more common genetic diseases and its sex determined from just a whole blood sample from the pregnant mother. Fetal DNA is abundant enough in the systemic ...
4
votes
1answer
507 views

Miscarriage in early humans

Today, about 10 to 20 percent of known pregnancy end in miscarriage. Pregnancy is a biological process that has been very well studied by medicine. As a result, modern medicine helps a lot to prevent ...
1
vote
1answer
5k views

Can ovulation and menstruation occur simultaneously?

Is that possible that ovulation happens in the time of actual menstrual haemorrhage in human females - let say in a case that woman has 21 day cycle and her menstrual period is 7 days? If yes, does ...
0
votes
0answers
149 views

Does a pregnant female body treat the fetus based on gender?

I have seen on a youtube video that the female body produces antigenes and antibodies when she is pregnant with a boy. But this behaviour is not produced when she is pregnant with a girl. These means ...
5
votes
2answers
163k views

Teens concerned about impregnation through clothes

Dry Humping, is: dry humping is the process of two people repeatedly moving up and down and back and forth on top of each other fully clothed( or missing various pieces, but the penis must not come ...
6
votes
1answer
842 views

How common is it to be pregnant with periods?

As you may know, some women claim that they have their period while they are pregnant. In the arab world they call it "Deer pregnancy", since when the deer gets pregnant, it still gets its' monthly ...
1
vote
1answer
188 views

Mutated Sperm - What happens?

I saw on TV that not all sperm are the same. Some have mutations like 2 and 3 tails? There were other mutations as well. If one of these mutated sperm actually fertilized an egg, would the embryo ...
4
votes
1answer
156 views

Erythroblastosis Foetalis

If Rh- mother has Rh+ baby, the mother can become sensitized during first pregnancy and then if subsequent fetuses are also Rh+, there can be eryhtroblastosis foetalis. I read that if mother is O- ...