Template:Third Trimester Timeline

From Embryology
Third Trimester Timeline 
Timeline human development | First Trimester Timeline | Second Trimester Timeline | Third Trimester Timeline
Week
Stage
Event
Clinical third trimester (GA Clinical Week 28) Third Trimester Fetal size change.jpg Hearing 3rd Trimester - vibration acoustically of maternal abdominal wall induces startle respone in fetus.
27
 
28
  Respire Month 7 - respiratory bronchioles proliferate and end in alveolar ducts and sacs
29
 

Tooth Development Week 29 - Permanent premolars (correspond to the milk molars) appear.

30
   

Genital male gonad (testes) descending

31
 
32
  Nail Development fingernails reach digit tip
33
  Neural brain cortical sulcation - primary sulci present[1]
34
  Neural brain cortical sulcation - insular, cingular, and occipital secondary sulci present[1]
35
   
36
  Frazer006 bw600.jpg Nail Development toenails reach digit tip

Lens Development - lens growth and interocular distance plateaus after 36 weeks of gestation[2]

37
   
38
Birth Newborn.jpg Clinical Week 40

Heart pressure difference closes foramen ovale leaving a fossa ovalis

Thyroid TSH levels increase, thyroxine (T3) and T4 levels increase to 24 h, then 5-7 days postnatal decline to normal levels

Adrenal - zona glomerulosa, zona fasiculata present

  1. 1.0 1.1 C Garel, E Chantrel, H Brisse, M Elmaleh, D Luton, J F Oury, G Sebag, M Hassan Fetal cerebral cortex: normal gestational landmarks identified using prenatal MR imaging. AJNR Am J Neuroradiol: 2001, 22(1);184-9 PubMed 11158907
  2. L B Paquette, H A Jackson, C J Tavaré, D A Miller, A Panigrahy In utero eye development documented by fetal MR imaging. AJNR Am J Neuroradiol: 2009, 30(9);1787-91 PubMed 19541779