Sorry about that, message received going forward.  I guess I thought this particular entry might be more controversial, and I guess it wasn't. Thank you for the feedback.

prog, wisdom

Brian, you don't need to post so many examples. If you come across a dubious use of adj-no, just remove it and leave a comment saying that the word doesn't appear to be adjectival. The editors will almost certainly agree. There are thousands of kango entries with adj-no tags that should be removed.

@@ -23 +23,2 @@
-<gloss>unborn child</gloss>
+<gloss>baby in the womb</gloss>
+<gloss>unborn baby</gloss>

@@ -20 +19,0 @@
-<pos>&adj-no;</pos>

胎児の	179854 <-- fetus
幼児の	471106 <-- toddler


胎児の発育	8387	 <--- fetus ("fetal growth/development")
幼児の発育	1226     <--- toddler ("the toddler's growth/development")

胎児の成長	8299	  
幼児の成長	2067

胎児の耳	8275	  
幼児の耳	387

胎児の時	3951	  
幼児の時	3421

胎児の健康	3831	 fetal health/the fetus's health
幼児の健康	2453     toddler's health

胎児の心拍	3320	  
幼児の心拍	34    (heartbeat less of a concern)

胎児の脳	3228	  
幼児の脳	2435   (brain still matters...)


胎児の正常な発育	3213	 "the baby's/fetus's normal development"

胎児の記憶	3043	 
幼児の記憶	954
 
胎児の状態	3025	  "the fetus's condition" (not "fetal")

胎児の大きさ	2699	  
胎児の世界	2696	  
胎児の頭	2197	  
etc.

Should [adj-no] be dropped here?

Perhaps this is better left alone for practical reasons.  But if "胎児" is literally "the child in the womb", is this [adj-no]?  Just because we have "fetal" in English as an adjective. "fetus's heartbeat", "fetal heartbeat". 

Compare: 幼児 (toddler, not [adj-no]).  (I've taken the top 胎児の ngrams, and matched them with 幼児 in the refs). The potential usage seems almost identical.

There are also a number of nouns prefixed with 胎児, just as there are with 幼児.  Here's one that got an adj. gloss: 幼児退行: infantile regression