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Pregnancy Timeline by SemestersDevelopmental TimelineFertilizationFirst TrimesterSecond TrimesterThird TrimesterFirst Thin Layer of Skin AppearsEnd of Embryonic PeriodEnd of Embryonic PeriodFemale Reproductive SystemBeginning Cerebral HemispheresA Four Chambered HeartFirst Detectable Brain WavesThe Appearance of SomitesBasic Brain Structure in PlaceHeartbeat can be detectedHeartbeat can be detectedFinger and toe prints appearFinger and toe prints appearFetal sexual organs visibleBrown fat surrounds lymphatic systemBone marrow starts making blood cellsBone marrow starts making blood cellsInner Ear Bones HardenSensory brain waves begin to activateSensory brain waves begin to activateFetal liver is producing blood cellsBrain convolutions beginBrain convolutions beginImmune system beginningWhite fat begins to be madeHead may position into pelvisWhite fat begins to be madePeriod of rapid brain growthFull TermHead may position into pelvisImmune system beginningLungs begin to produce surfactant
CLICK ON weeks 0 - 40 and follow along every 2 weeks of fetal development


ZIKA in Men? "No procreation for 6 months"

The Zika virus has largely spread via mosquitoes, but it can also be spread by sexual intercourse. Men who may have been exposed should wait at least six months before trying to conceive a child with a partner. Regardless whether they ever had any symptoms, say US federal health officials.

Previously, The Centers for Disease Control and Prevention had suggested that only men with Zika symptoms had to wait 6 months. Those who may have been exposed to Zika but never developed any symptoms were told to hold off on trying to conceive for just eight weeks.

But on Friday, September 30, 2016 the CDC published revised recommendations based on new evidence indicating the Zika virus can remain in semen longer than had been thought and can be spread by men even if they don't have symptoms.

"The updated recommendations incorporate what's been learned since the previous guidance was released. The new time period for couples to wait before attempting conception — when the man has possible Zika exposure but with no symptoms — is expected to minimize the risk of sexual transmission at the time of conception and prevent possible early fetal exposure to the Zika virus."

The Centers for Disease Control and Prevention, United States of America

The Zika virus can cause a variety of birth defects when women get infected while pregnant. The most serious linked to Zika is microcephaly, which causes babies to be born with abnormally small heads and badly damaged brains.

For couples planning to conceive but who do not live in a place where the virus is actively spreading, the CDC recommends men who may have been exposed while traveling where the virus is active — wait at least six months before trying to conceive.

The virus has spread in Latin America, especially Brazil, and the Caribbean including Puerto Rico. It has also been spread by mosquitoes in the Pacific islands such as Fiji.

For couples who live in a place where the virus is spreading, the CDC recommends both sexes should be tested if they develop any symptoms.

  • Men who test positive should wait at least six months to try to conceive.
  • Women who test positive should wait at least eight weeks.

Those who test negative should consult with their doctor.

The guidelines are less specific for couples who live in a place such as Miami experiencing an outbreak, but who don't have any reason to believe they may have been infected.

The guidelines recommend that any concern for exposure should induce those couples talk their doctors about what to do, weigh factors that "might influence pregnancy timing," including age of each parent and if they have had problems getting pregnant previously.

Congress Ends Spat
Agrees To Fund $1.1 Billion
To Combat Zika

The agency stressed that its guidelines will continue to change as new information about Zika becomes available as the virus has repeatedly surprised health authorities. At first they thought the virus was only transmitted by mosquitoes. Now researchers have discovered men can spread Zika to women through sexual contact. The CDC was surprised again when doctors determined women could also spread the virus sexually to men.

The Food and Drug Administration recently recommended that all blood donations be screened for the virus to minimize the chances pregnant women might be infected by transfusion, or sex with someone who had a transfusion.

CDC Announcement
Update: Interim Guidance for Preconception Counseling and Prevention of Sexual Transmission of Zika Virus for Persons with Possible Zika Virus Exposure — United States, September 2016

C DC has updated its interim guidance for persons with possible Zika virus exposure who are planning to conceive (1) and interim guidance to prevent transmission of Zika virus through sexual contact (2), now combined into a single document. Guidance for care for pregnant women with possible Zika virus exposure was previously published (3). Possible Zika virus exposure is defined as travel to or residence in an area of active Zika virus transmission (http://www.cdc.gov/zika/geo/index.html), or sex* without a condom† with a partner who traveled to or lived in an area of active transmission. Based on new though limited data, CDC now recommends that all men with possible Zika virus exposure who are considering attempting conception with their partner, regardless of symptom status,§ wait to conceive until at least 6 months after symptom onset (if symptomatic) or last possible Zika virus exposure (if asymptomatic). Recommendations for women planning to conceive remain unchanged: women with possible Zika virus exposure are recommended to wait to conceive until at least 8 weeks after symptom onset (if symptomatic) or last possible Zika virus exposure (if asymptomatic). Couples with possible Zika virus exposure, who are not pregnant and do not plan to become pregnant, who want to minimize their risk for sexual transmission of Zika virus should use a condom or abstain from sex for the same periods for men and women described above. Women of reproductive age who have had or anticipate future Zika virus exposure who do not want to become pregnant should use the most effective contraceptive method that can be used correctly and consistently. These recommendations will be further updated when additional data become available.

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Oct 4, 2016   Fetal Timeline   Maternal Timeline   News   News Archive   

ZIKA in the USA.
Image Credit:
The Centers for Disease Control and Prevention


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