All four of the Americans advanced out of the first round of the women's 400m hurdles at the IAAF World Championships Monday in London. 

Olympic champion Dalilah Muhammad ran the fastest time of the day with a dominating win out of heat one. She secured an automatic spot into the semifinal with a time of 54.59. 2015 World bronze medalist Cassandra Tate cruised to a third-place finish in heat two. Despite breaking a hurdle in half during the final moments of heat three, Shamier Little finished third to earn an automatic spot. And Kori Carter eased up to win heat four in 54.99. 

Full list of semifinal qualifiers:

POS	ATHLETE	COUNTRY	RESULTS
1	Dalilah MUHAMMAD	USA	54.59 Q
2	Ristananna TRACEY	JAM	54.92 Q
3	Kori CARTER	USA	54.99 Q
4	Zuzana HEJNOVÁ	CZE	55.05 Q
5	Sage WATSON	CAN	55.06 Q
6	Léa SPRUNGER	SUI	55.14 Q
7	Rhonda WHYTE	JAM	55.18 Q
8	Sara Slott PETERSEN	DEN	55.23 Q
9	Glory Onome NATHANIEL	NGR	55.30 Q PB
10	Denisa ROSOLOVÁ	CZE	55.41 Q SB
11	Sparkle MCKNIGHT	TTO	55.46 Q SB
12	Wenda NEL	RSA	55.47 Q
13	Cassandra TATE	USA	55.48 Q
14	Eilidh DOYLE	GBR	55.49 Q
15	Ayomide FOLORUNSO	ITA	55.65 Q SB
16	Petra FONTANIVE	SUI	56.13 Q
17	Leah NUGENT	JAM	56.16 q
18	Shamier LITTLE	USA	56.18 Q
19	Joanna LINKIEWICZ	POL	56.18 q
20	Grace CLAXTON	PUR	56.35 Q
21	Yadisleidis PEDROSO	ITA	56.41 q
22	Meghan BEESLEY	GBR	56.41 q
23	Amalie IUEL	NOR	56.42
24	Zurian HECHAVARRÍA	CUB	56.44
25	Lauren WELLS	AUS	56.49
26	Gianna WOODRUFF	PAN	56.50 Q
27	Agata ZUPIN	SLO	56.54 Q
28	Olena KOLESNYCHENKO	UKR	56.88
29	Marzia CARAVELLI	ITA	56.92
30	Jessica TURNER	GBR	56.98
31	Viktoriya TKACHUK	UKR	57.05
32	Aminat YUSUF JAMAL	BRN	57.41
33	Noelle MONTCALM	CAN	57.45
34	Jackie BAUMANN	GER	57.59
35	Déborah RODRÍGUEZ	URU	57.61 SB
36	Yasmin GIGER	SUI	57.72
37	Tia-Adana BELLE	BAR	58.82
38	Drita ISLAMI	MKD	1:00.38
39	Kristina PRONZHENKO	TJK	1:03.44